This clinical research study proposes to determine how a dose of a new contrast agent called Iomeprol (iomeron) circulates through the body and is excreted after it is injected in patients 65 years of age and older. A contrast agent is used when a person has computed tomography (CT) of the body to better see blood vessels and other structures inside the body. The contrast agent is given as an injection into a blood vessel. The contrast agent remains in the blood while the imaging is taking place. The majority of the contrast agent leaves the body through urine and the rest is excreted in the feces. Participation in the trial will last approximately 4 days, beginning at least 12-24 hours before the procedure and will last until 72 hours after the procedure. Just prior to the study, the patient will have a complete physical exam, and tests of the heart (electrocardiogram), and blood. These same tests will be done again 24 and 72 hours after the procedure. Blood samples will be taken to obtain hematology and serum chemistry values. In addition, blood and urine samples will be taken to determine the level of Iomeprol that remains in these samples at specified time points. Blood samples will be taken beginning 5 minutes before the procedure and throughout the 72 hour period post body CT. A total of 15 samples will be taken for Iomeprol levels. In total, the amount of blood withdrawn will be no more than 8 tablespoons. Urine samples will be collected from 12 hours prior to body CT and throughout the 72 hour period post body CT.